1. Field of the Invention
The present invention relates to a forming die for forming a cushion member used in the seat of vehicle or automobile and so forth, and in particular relates to a forming die for forming a foam cushion member on its surface with a female pile-type fastener adapted to be engageable with a mating male one provided on the back surface of a top cover member associated with the seat.
2. Description of the Prior Art
There has been such a cushion member which is formed by foaming a foamable material (polyurethane, for example) integrally on its surface with a female pile-type fastener (a loop part of a hook-and-loop fastener, for example). What is meant by such pile-type fastener as defined hereby includes all kinds of hook-and-loop fasteners known as "Velcro" (registered trade mark) and all similar types of fasteners, or the like. Referring to FIG. 2 in the accompanying drawings, is illustrative of this kind of resultant cushion member (A) with a plurality of female pile-type fasteners (a) integrally provided therein. As seen in this figure, a corresponding number of plural male pile-type fasteners (a') (a hook part of the hook-and-loop fastener, for example) are provided on the back surface of a top cover member (B). Upon engaging the male pile-type fasteners with the female ones, the top cover member (B) is brought to a close contact with the cushion member (A), so that the former is stretched in conformity with the contour of the latter. Accordingly, this kind of seat construction is advantageous in that it is far improved in its assembling process as compared with a seat of such type wherein a top cover member is fixed to a cushion member by inserting a securing string provided on the back surface of the top cover member into the cushion member.
Conventionally, the above-described cushion member with the plural female pile-type fasteners (a) has been formed by means of a forming die of such construction that there is embedded a permanent magnet in a recessed groove formed in the die for the purpose of securing a pile-type fastener to the die under the influence of magnetic force. According to this conventional die, after the pile-type fastener has been secured by the magnet, a foam material in fluid is injected into the forming die, and then a foaming is effected within the die so as to form a predetermined shape of cushion member together with the pile-type fastener.
Such conventional forming die, however, involves the following drawbacks: (a) A material to be attracted to the magnet in the die, such as a ferrous metallic material, needs to be provided in the pile-type fastener for magnetically securing the pile-type fastener to the die. Consequently, assembling the fastener requires rather troublesome steps with high costs involved, and further, the magnetically attractable material (ferrous metallic material) is of hard nature and provided in the fastener on the cushion member, with the result that it deteriorates the cushioning effect of the cushion member and gives a poor seating touch to an occupant thereon. (b) A magnet with a great magnetic force is required in order that it can transmit a sufficient attractive force through the layer of the pile-type fastener so as to positively secure the fastener to the forming die.